646444444646 has 256 divisors, whose sum is σ = 1387098058752. Its totient is φ = 217755648000.

The previous prime is 646444444621. The next prime is 646444444699.

646444444646 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 646444444591 and 646444444600.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 451111946 + ... + 451113378.

It is an arithmetic number, because the mean of its divisors is an integer number (5418351792).

Almost surely, 2^646444444646 is an apocalyptic number.

646444444646 is an abundant number, since it is smaller than the sum of its proper divisors (740653614106).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

646444444646 is a wasteful number, since it uses less digits than its factorization.

646444444646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1687.

The product of its digits is 84934656, while the sum is 56.

The spelling of 646444444646 in words is "six hundred forty-six billion, four hundred forty-four million, four hundred forty-four thousand, six hundred forty-six".